There are grass liveries at our yard, and they are charged a summer price, and a winter price. The winter price is £5 more per week and it includes hay.
They've started haying already, but the mild weather means they don't need much at the moment. The grass livery fields are quite large with reasonable grass cover all year round.
Last year, during that prolonged snowy period, the YO didn't cover her costs as they needed more than £5 of hay per week, so it might go up if there's snow this year.